The invention relates to the field of inkjet ink receptacles.
Inkjet ink is used often in assembly lines to label products such as packages and magazines. Maintenance of such inkjet printers and replenishment of their ink supply must be done quickly and efficiently so as to minimize adverse affects on progress of the assembly line. Further, handling of inkjet ink is particularly dangerous, since such ink may be toxic and highly staining in the event of spills.
Ink for assembly line inkjet printers is often delivered by re-usable ink bottles which feed into inkjet ink receptacles, from which ink is drawn for printing. An example of such an application is illustrated in U.S. Pat. No. 5,343,226, the disclosure of which is incorporated herein by reference. In such an application, it is common to insert the inkjet ink bottle, cap down, into the receptacle. So that the cap need not be removed from the bottle to allow the ink to flow, the receptacle passageway may exhibit a pin which, upon insertion of the cap into the receptacle, depresses a spring-loaded plunger in the cap. The displacement of the plunger unseals a passageway in the cap, allowing the inkjet ink to flow downward from the bottle, through the cap and into the receptacle, from where the inkjet printer may draw the ink. Upon removal of the inkjet ink bottle and cap from the receptacle, the spring-loaded plunger reseals the cap, preventing the ink from flowing out of the bottle.
A problem with the spring-loaded plunger caps of the prior art is that springs may break or weaken over time, which is particularly undesirable if the cap is to be re-used many times. The present invention provides an alternative sealing mechanism using magnets.
There is disclosed herein an inkjet ink bottle cap including a mechanism for locking the cap in a receptacle, a passageway for receiving a displacement pin upon inserting the cap in a receptacle, and a displaceable magnetic seal. The magnetic seal may comprise a ball and sealing seat having a magnetic attraction to each other, and the ball may be displaced by the displacement pin. The magnetic seal may further comprise two sealable seal plates having a magnetic attraction to each other and one of the two plates fixed to a plunger. The plates may be displaced from each by displacement of the plunger by the pin upon insertion of the cap into the passageway. In any embodiment, the magnetic seal re-seals by magnetic attraction upon removal of the cap from the passageway and, thus, removal of the displacement pin from the cap.